binutils: inherit {build,host,target}Platform to avoid repeating ourselves

pkgs/development/tools/misc/binutils/default.nix

@@ -27,13 +27,10 @@ assert enableGold -> execFormatIsELF stdenv.targetPlatform;
 
 
 let
+  inherit (stdenv) buildPlatform hostPlatform targetPlatform;
   reuseLibs = enableShared && withAllTargets;
 
   version = "2.37";
-  # The targetPrefix prepended to binary names to allow multiple binuntils on the
-  # PATH to both be usable.
-  targetPrefix = lib.optionalString (stdenv.targetPlatform != stdenv.hostPlatform)
-  "${stdenv.targetPlatform.config}-";
 
   srcs = {
     # HACK to ensure that we preserve source from bootstrap binutils to not rebuild LLVM
@@ -48,13 +45,17 @@ let
       sha256 = "1kdrz6fki55lm15rwwamn74fnqpy0zlafsida2zymk76n3656c63";
     };
   };
+
+  # The targetPrefix prepended to binary names to allow multiple binuntils on
+  # the PATH to both be usable.
+  targetPrefix = lib.optionalString (targetPlatform != hostPlatform) "${targetPlatform.config}-";
 in
 
 stdenv.mkDerivation {
   pname = targetPrefix + "binutils";
   inherit version;
 
-  src = srcs.${stdenv.targetPlatform.system} or srcs.normal;
+  src = srcs.${targetPlatform.system} or srcs.normal;
 
   # WARN: this package is used for bootstrapping fetchurl, and thus cannot use
   # fetchpatch! All mutable patches (generated by GitHub or cgit) that are
@@ -74,7 +75,7 @@ stdenv.mkDerivation {
     # Remove on the next release
     # https://sourceware.org/bugzilla/show_bug.cgi?id=28138
     ./fix-ld-descriptors.patch
-  ] ++ lib.optional stdenv.targetPlatform.isiOS ./support-ios.patch
+  ] ++ lib.optional targetPlatform.isiOS ./support-ios.patch
     # This patch was suggested by Nick Clifton to fix
     # https://sourceware.org/bugzilla/show_bug.cgi?id=16177
     # It can be removed when that 7-year-old bug is closed.
@@ -82,8 +83,8 @@ stdenv.mkDerivation {
     # GHC will refuse to compile with a binutils suffering from it. See this
     # comment for more information:
     # https://gitlab.haskell.org/ghc/ghc/issues/4210#note_78333
-    ++ lib.optional (stdenv.targetPlatform.isAarch32 && stdenv.hostPlatform.system != stdenv.targetPlatform.system) ./R_ARM_COPY.patch
-    ++ lib.optional stdenv.targetPlatform.isWindows ./windres-locate-gcc.patch;
+    ++ lib.optional (targetPlatform.isAarch32 && hostPlatform.system != targetPlatform.system) ./R_ARM_COPY.patch
+    ++ lib.optional targetPlatform.isWindows ./windres-locate-gcc.patch;
 
   outputs = [ "out" "info" "man" ];
 
@@ -92,9 +93,9 @@ stdenv.mkDerivation {
     bison
     perl
     texinfo
-  ] ++ (lib.optionals stdenv.targetPlatform.isiOS [
+  ] ++ (lib.optionals targetPlatform.isiOS [
     autoreconfHook
-  ]) ++ lib.optionals stdenv.targetPlatform.isVc4 [ flex ];
+  ]) ++ lib.optionals targetPlatform.isVc4 [ flex ];
   buildInputs = [ zlib gettext ];
 
   inherit noSysDirs;
@@ -114,7 +115,7 @@ stdenv.mkDerivation {
 
   # As binutils takes part in the stdenv building, we don't want references
   # to the bootstrap-tools libgcc (as uses to happen on arm/mips)
-  NIX_CFLAGS_COMPILE = if stdenv.hostPlatform.isDarwin
+  NIX_CFLAGS_COMPILE = if hostPlatform.isDarwin
     then "-Wno-string-plus-int -Wno-deprecated-declarations"
     else "-static-libgcc";
 
@@ -161,7 +162,7 @@ stdenv.mkDerivation {
   '';
 
   # else fails with "./sanity.sh: line 36: $out/bin/size: not found"
-  doInstallCheck = stdenv.buildPlatform == stdenv.hostPlatform && stdenv.hostPlatform == stdenv.targetPlatform;
+  doInstallCheck = buildPlatform == hostPlatform && hostPlatform == targetPlatform;
 
   enableParallelBuilding = true;